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Abstract:

Provided are a method for managing radio resources according to a type of
data and user equipment using the same. In the method, a paging message
may be received from a radio access network. A cause of the paging
message may be determined. A timer may be set for releasing radio
resources according to the determined cause of the paging message. When
the timer expires, radio resources may be released.

Claims:

1. A method for managing radio resources according to a type of data, the
method comprising: receiving a paging message; determining a cause for
the paging message; setting a period of a timer for releasing radio
resources according to the determined cause of the paging message; and
releasing the radio resources when the timer expires.

2. The method of claim 1, comprising: receiving the paging message when
user equipment is in an idle mode; transitioning, by the user equipment,
from the idle mode to a connected mode after receiving the paging
message; and establishing a radio connection to a radio communication
network when the user equipment transitions from the idle mode to a
connected mode.

3. The method of claim 1, wherein the determined cause of the paging
message is based on a paging cause included in the paging message.

5. The method of claim 1, wherein the determining a cause of the paging
message includes: examining a paging cause included in the paging
message; and determining that the paging message relates to a push data
when the cause of the paging message is terminating interactive call.

6. The method of claim 5, wherein the setting the period of the timer
includes: setting the timer with a comparatively short time period when
the paging message relates to the push data.

7. The method of claim 1, wherein, for setting the period of the timer,
the tinier is a signal connection release indication (SCRI) timer.

8. The method of claim 7, wherein the releasing radio resources includes:
transmitting a SCRI message to a radio access network; and releasing
radio resources allocated when establishing a radio connection from user
equipment to a radio communication network in response to the SCRI
message.

9. The method of claim 8, wherein the radio connection is at least one of
a radio resource control (RRC) connection, a radio bearer, and a radio
access bearer (RAB) connection.

10. The method of claim 1, wherein, after the determining the cause of
the paging message, further comprising: transitioning from an idle mode
to a connected mode by establishing a radio connection to a radio
communication network; transmitting a paging response message through the
radio connection in response to the paging message; releasing the radio
connection by the releasing radio resources when the timer expires; and
transitioning from the connected mode to the idle mode.

11. A method for managing radio resources for a push data, the method
comprising: receiving a paging message when user equipment is in an idle
mode; establishing a radio connection from the user equipment and a radio
communication network; transmitting a paging response message to the
radio communication network through the established radio connection;
determining whether a cause of the received paging message is the push
data; setting a signal connection release indication (SCRI) timer based
on the determination result; and releasing the radio connection when the
SCRI timer expires.

12. The method of claim 11, wherein the radio connection is a radio
resource control (RRC) connection between the user equipment and a radio
network controller.

13. The method of claim 11, wherein the cause of the received paging
message is based on a paging cause included in the paging message.

14. The method of claim 13, wherein: the cause of the received paging
message includes at least one of terminating conversation call,
terminating streaming call, terminating interactive call, terminating
background call, terminating high priority signaling, and
terminating-cause unknown; and the cause of the received paging message
is determined as a push data when the cause of the received paging
message is the terminating interactive call.

15. The method of claim 11, wherein the releasing the radio connection
includes: transmitting a SCRI message to a radio network controller when
the timer expires; releasing a radio resource control (RRC) connection to
the radio network controller in response to the SCRI message; and
transitioning from the connected mode to an idle mode.

16. User equipment for managing radio resources according to a type of
data, the user equipment configured to: receive a paging message from a
radio access network; determine a cause of the received paging message;
set a period of a timer for releasing radio resources according to the
determined cause of the paging message; and release the radio resources
when the timer expires:

17. The user equipment of claim 16, wherein the user equipment receives
the paging message when the user equipment is in an idle mode,
transitions from the idle mode to a connected mode by establishing a
radio resource control (RRC) connection to a radio network controller,
and transmits a paging response message to the radio network controller
through the radio connection.

18. The user equipment of claim 16, wherein the user equipment determines
the cause of the received paging message based on a paging cause included
in the received paging message.

19. The user equipment of claim 18, wherein: the paging cause includes at
least one of terminating conversation call, terminating streaming call,
terminating interactive call, terminating background call, terminating
high priority signaling, and terminating-cause unknown; and the user
equipment determines that the paging message is caused by the push data
when the cause of the paging message is terminating interactive call.

20. The user equipment of claim 16, wherein the user equipment: sets the
period of the timer with a comparatively short time period when the
paging message is caused by the push data; transmits a signal connection
release indication (SCRI) message to the radio access network; releases a
radio resource control (RRC) connection to a radio network controller
when the timer expires; and transitions from a connected mode to an idle
mode.

Description:

CROSS REFERENCE TO PRIOR APPLICATIONS

[0001] The present application claims priority under 35 U.S.C. §119
to Korean Patent Application No. 10-2011-0012886 (filed on Feb. 14,
2011), which is hereby incorporated by reference in its entirety.

FIELD OF THE INVENTION

[0002] The present invention relates to managing radio resources and, in
particular, to managing radio resources according to a type of data in a
communication network.

BACKGROUND OF THE INVENTION

[0003] Lately, demands for a push data service have abruptly increased as
smart-phones have become popular among users of communications devices.
The push data service may automatically distribute various types of
information to user equipment using push technology. In the push data
service, a request for transmission of information may be initiated by a
related server, which is coupled with a pull data service where the
request for the transmission of information is initiated by a receiver or
a client. Such push data service may provide information such as
advertisements, news articles, and e-mails in a form of a push message.

[0004] A radio connection may be established between user equipment and a
communication network when data traffic is generated to be transmitted or
received. In order to efficiently utilized limited radio resources in a
communication network, such a radio connection may be managed based on a
radio resource control (RRC) protocol. For example, a RRC connection
between user equipment and a radio network controller may be established
when data traffic is generated between the user equipment and the radio
network controller. The RRC connection may be released when data traffic
is not generated for a given time period.

[0005] In general, push data may not necessarily require user equipment to
transmit another data in response to the push data. For example, when
user equipment receives an advertisement as the push data, the user
equipment is not required to transmit a response message when it receives
such push data. That is, a RRC connection between the user equipment and
a communication network is not necessarily maintained after receiving the
push data. If the RRC connection is released when a given time period
passes after the push data is received, related radio resources may be
wasted.

SUMMARY OF THE INVENTION

[0006] Embodiments of the present invention overcome the above
disadvantages and other disadvantages not described above. Also, the
present invention is not required to overcome the disadvantages described
above, and an embodiment of the present invention may not overcome any of
the problems described above.

[0007] In accordance with an aspect of the present invention, radio
resources may be managed according to a type of data associated with user
equipment.

[0008] In accordance with another aspect of the present invention, radio
resources may be released immediately after receiving a push data.

[0009] In accordance with another aspect of the present invention, a timer
for a transmitting a signal connection release indication (SCRI) message
may be set differently according to a type of data received at user
equipment. When the tinier expires, a SCRI message is transmitted.

[0010] In accordance with an exemplary embodiment of the present
invention, a method is provided for managing radio resources according to
a type of data. The method may include receiving a paging message,
determining a cause for the paging message, setting a period of a timer
for releasing radio resources according to the determined cause of the
paging message, and releasing the radio resources when the timer expires.

[0011] The method may include receiving the paging message when user
equipment is in an idle mode, transitioning, by the user equipment, from
the idle mode to a connected mode after receiving the paging message, and
establishing a radio connection to a radio communication network when the
user equipment transitions from the idle mode to a connected mode. The
determined cause of the paging message may be based on a paging cause
included in the paging message.

[0013] The determining a cause of the paging message may include examining
a paging cause included in the paging message, and determining that the
paging message relates to a push data when the cause of the paging
message is terminating interactive call.

[0014] The setting the period of the timer may includes setting the timer
with a comparatively short time period when the paging message relates to
the push data.

[0015] For setting the period of the timer, the timer may be a signal
connection release indication (SCRI) timer.

[0016] The releasing radio resources may include transmitting a SCRI
message to a radio access network, and releasing radio resources
allocated when establishing a radio connection from user equipment to a
radio communication network in response to the SCRI message.

[0017] The radio connection may be at least one of a radio resource
control (RRC) connection, a radio bearer, and a radio access bearer (RAE)
connection.

[0018] After the determining the cause of the paging message, the method
may further include transitioning from an idle mode to a connected mode
by establishing a radio connection to a radio communication network,
transmitting a paging response message through the radio connection in
response to the paging message, releasing the radio connection by the
releasing radio resources when the timer expires, and transitioning from
the connected mode to the idle mode.

[0019] In accordance with another embodiment of the present invention, a
method may be provided for managing radio resources for a push data. The
method may include receiving a paging message when user equipment is in
an idle mode, establishing a radio connection from the user equipment and
a radio communication network, transmitting a paging response message to
the radio communication network through the established radio connection,
determining whether a cause of the received paging message is the push
data, setting a signal connection release indication (SCRI) timer based
on the determination result, and releasing the radio connection when the
SCRI timer expires.

[0020] The radio connection may be a radio resource control (RRC)
connection between the user equipment and a radio network controller. The
cause of the received paging message may be based on a paging cause
included in the paging message.

[0021] The cause of the received paging message may include at least one
of terminating conversation call, terminating streaming call, terminating
interactive call, terminating background call, terminating high priority
signaling, and terminating-cause unknown. Such cause of the received
paging message may be determined as a push data when the cause of the
received paging message is the terminating interactive call.

[0022] The releasing the radio connection may include transmitting a SCRI
message to a radio network controller when the timer expires, releasing a
radio resource control (RRC) connection to the radio network controller
in response to the SCRI message, and transitioning from the connected
mode to an idle mode.

[0023] In accordance with another embodiment of the present invention,
user equipment is provided for managing radio resources according to a
type of data. The user equipment may be configured to receive a paging
message from a radio access network, determine a cause of the received
paging message, set a period of a timer for releasing radio resources
according to the determined cause of the paging message, and release the
radio resources when the timer expires.

[0024] The user equipment may receive the paging message when the user
equipment is in an idle mode, transition from the idle mode to a
connected mode by establishing a radio resource control (RRC) connection
to a radio network controller, and transmit a paging response message to
the radio network controller through the radio connection.

[0025] The user equipment may determine the cause of the received paging
message based on a paging cause included in the received paging message.

[0026] The user equipment may set the period of the timer with a
comparatively short time period when the paging message is caused by the
push data, transmit a signal connection release indication (SCRI) message
to the radio access network, release a radio resource control (RRC)
connection to a radio network controller when the timer expires; and
transition from a connected mode to an idle mode.

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The above and/or other aspects of the present invention will become
apparent and more readily appreciated from the following description of
embodiments, taken in conjunction with the accompanying drawings, of
which:

[0028] FIG. 1 illustrates a radio communication network employing one or
more exemplary embodiments of the present invention;

[0029] FIG. 2 illustrates RRC mode and mode transitions as might be
employed with embodiments of the present invention;

[0030] FIG. 3 illustrates a typical method for managing radio resources
when data is transmitted to user equipment in an idle mode;

[0031] FIG. 4 illustrates user equipment for managing radio resources
according to a type of data in accordance with an exemplary embodiment of
the present invention; and

[0032] FIG. 5 illustrates a method for managing radio resources according
to a type of data in accordance with an exemplary embodiment of the
present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0033] Reference will now be made in detail to embodiments of the present
invention, examples of which are illustrated in the accompanying
drawings, wherein like reference numerals refer to like elements
throughout. The embodiments are described below, in order to explain the
present invention by referring to the figures.

[0034] For convenience and ease of understanding, a method for managing
radio resources according to a type of data in accordance with an
exemplary embodiment of the present invention will be described as
managing radio resources in a 3rd generation partnership project
universal mobile telecommunication system (3GPP UMTS) network. The
present invention, however, is not limited thereto. For example, a system
may manage radio resources in a global system for mobile communication
(GSM) or through a tong term evolution (LTE) advanced network in
accordance with other embodiments.

[0035] FIG. 1 illustrates a radio communication network employing one or
more exemplary embodiments of the present invention.

[0036] Referring to FIG. 1, communication network 100 may include several
user equipment 110-1 to 110-3, base station 120, radio network controller
(RNC) 130, serving general packet radio service (GPRS) support node
(i.e., "SGSN") 1140, and Internet 150.

[0037] One or more of user equipment 110-1, 110-2, and 110-3 may be
connected to Internet 150 through a radio communication network including
base station 120, RNC 130, and SGSN 140. Each of user equipment 110-1,
110-2, and 110-3 may receive data from and/or transmit data to entities
on Internet 150 through the radio communication network. In order to
transfer data, each of user equipment 110-1 to 110-3 may establish a
corresponding radio connection to SGSN 140. For example, radio
connections may include a radio resource control (RRC) connection and a
radio access bearer (RAB) connection. The RRC connection may be formed
between one or more of user equipment 110-1 to 110-3 and RNC 130, and the
RAB connection may be formed between RNC 130 and SGSN 140.

[0038] Base station 120 may be directly connected user equipment 110-1 to
110-3 and transfer data between each of user equipment 110-1 to 110-3 and
RNC 130. For example, base station 120 may receive a radio signal from
one of user equipment 110-1 to 110-3, convert the radio signal to a
baseband signal, and transmit the baseband signal to RNC 130.
Furthermore, base station 120 may receive a baseband signal from RNC 130,
convert the baseband signal to a radio signal, and transmit the radio
signal to one (or more, if a broadcast) of user equipment 110-1 to 110-3.

[0039] RNC 130 may be connected to base station 120 and manage radio
resources. RNC 130 may be a service access point connected to a core
network. For example, RNC 130 may perform allocation, modification, and
release of radio resources in a radio communication network. Furthermore,
RNC 130 may perform mobility management of user equipment 110-1 to 110-3.
For example, RNC 130 may manage mobility of user equipment 110-1 to 110-3
based on a RRC mode of a RRC protocol. For example, RNC 130 may manage
each RRC connection to user equipment 110-1 to 110-3. The RRP mode may
include a connected mode and an idle mode. RNC 130 may form a radio
access network with base station 120.

[0040] SGSN 140 may be a support node of a core network. SGSC 140 may
perform a role as a packet switching device in a core network. SGSC 140
may perform packet routing, packet transmission, and mobility management
such as an attach/detach process and local management, logical link
management and authentication for user equipment 110-1, 110-2, and 110-3.

[0041] As described above, the radio connections may be established
between user equipment 110-1 to 110-3 and SGSN 140 for receiving data
from and/or transmitting data to entities on Internet 150. Since radio
resources are limited in a communication network, such radio connections
may be released when no data requires transfer. In order to efficiently
manage the radio connections, a RRC protocol may be employed. The RRC
protocol may include a connected mode and an idle mode. The radio
connections may be managed according to the modes of the RRC protocol.
Hereinafter, the connected mode and the idle mode and transitions between
thereof will be described with reference to FIG. 2.

[0042] FIG. 2 illustrates RRC mode and mode transitions.

[0043] Referring to FIG. 2, a RRC protocol may define two modes: connected
mode 210 and idle mode 200. In idle mode 200, user equipment may be
powered off or a RRC connection between the user equipment and a radio
access network may not be established. In contrast, user equipment may be
connected to a radio access network when in connected mode 210. For
example, a RRC connection may be established between the user equipment
and the radio access network when in connected mode 210. In connected
mode 210, a RRC connection may be managed according to RRC states. The
RRC states may include a dedicated channel (Dell) state, a forward access
channel (FACH) state, and a paging channel (PCH) state. For example, a
dedicated channel may be allocated in the DCH state, and a shared channel
may be allocated in the FACH state. Furthermore, a paging channel may be
allocated in the PCH state.

[0044] Idle mode 200 may transition to connected mode 210 by establishing
a RRC connection between user equipment and a radio access network. In
contrast, connected mode 210 may transition to idle mode 200 by releasing
a RRC connection between user equipment and a radio access network.

[0045] In order to efficiently manage limited radio resources, radio
connections between user equipment and a radio communication network may
be released when no data requires transfer. In order to release such
radio connections, a signal connection release indication (SCRI) message
may be transmitted to RNC 130 when a given time period passes. In
response to the SCRI message, RNC 130 may release radio connections to
user equipment 110 and SGSN 140. Hereinafter, a typical method for
managing radio resources when downlink data is generated will be
described with reference to FIG. 3.

[0046] FIG. 3 illustrates a typical method for managing radio resources
when data is transmitted to user equipment in an idle mode.

[0047] Referring to FIG. 3, when SGSN 630 has data to be transmitted to
user equipment 610 in an idle mode, SGSN 630 may transmit a paging
message to user equipment 610 through RNC 620 at step S300. In response
to the paging message, a RRC connection may be established between user
equipment 610 and RNC 620 at step S310. The idle mode may transition to a
connected mode by establishing the RRC connection between user equipment
610 and RNC 620.

[0048] After establishing the RRC connection, user equipment 610 may
transmit a paging response message to SGSC 630 through RNC 620 at step
S320. In response to the paging response message, a radio access bearer
(RAB) connection may be established between RNC 620 and SGSN 630 at step
S330 and a radio bearer may be established between RNC 620 and user
equipment 610 at step S340. After establishing the radio bearer, user
equipment 610 may receive data from SGSN 630 through the established
connections at step S350.

[0049] When a given time period, T, expires after receiving the data, user
equipment 610 may transmit a signal connection release indication (SCRI)
message to RNC 620 in order to release the established connections at
step S360. The given time period. T, may be, for example, from about few
seconds to several tens of seconds.

[0050] In response to the SCRI message, RNC 620 may release the RAB
connection between RNC 620 and SGSN 630 at step S370 and release the RRC
connection between RNC 620 and user equipment 610 at step S380. User
equipment 610 may then transition from the connected mode to the idle
mode.

[0051] As illustrated in FIG. 3, user equipment 610 transmits the SCRI
message regardless of a type of the received data when the given time
period passes after receiving the data. Accordingly, the RRC connection
may not be released until the given time period passes although it is not
necessary to maintain the RRC connection. For example, in general, a push
data type of data does not necessarily require user equipment 610 to
transmit data in response to the push data. When user equipment 610
receives a push data, such as an advertisement, data is not present for
transmission in response to the push data. In this case, if the RRC
connection is maintained until the given time period passes, related
radio resources will be unnecessarily wasted. Accordingly, there is a
need for developing a method for managing radio resources when the
received data is push data.

[0052] In accordance with an exemplary embodiment of the present
invention, radio resources may be managed according to a type of data
transmitted to user equipment. For example, when the type of data
transmitted to the user equipment is a push data, a radio connection
between user equipment and a core network may be immediately released
after the user equipment receives the push data. To immediately release
such a connection, a timer for transmitting a SCRI message may be set
with a comparatively short time in accordance with an exemplary
embodiment of the present invention. Hereinafter, a method for managing
radio resources according to a type of data and user equipment using the
same will be described with reference to FIG. 4 and FIG. 5.

[0053] FIG. 4 illustrates user equipment for managing radio resources
according to a type of data in accordance with an exemplary embodiment of
the present invention.

[0054] When a radio access network has data to be transmitted to user
equipment 410 in an idle mode, the radio access network may transmit a
paging message to user equipment 410 in order to wake up user equipment
410 from the idle mode and transition to a connected mode. In accordance
with an exemplary embodiment of the present invention, user equipment 400
may determine a type of data based on a paging cause (an identified
event) included in the paging message and set a timer for releasing radio
resources based on the determination result.

[0056] Receiver 412 may receive a paging message from a radio access
network when user equipment 410 is in an idle mode. After receiving the
paging message, receiver 412 may transfer the paging message to timer
setup unit 416. Receiver 412 may receive data after a RRC connection is
established to a radio access network.

[0057] Timer setup unit 416 may receive the paging message from receiver
412. Timer setup unit 416 may determine a type of data to be received
based on the paging message. Particularly, timer setup unit 416 may
extract a paging cause included in the paging message and determine
whether the paging message is caused by a push message or not.

[0060] Timer setup unit 416 may set up a timer based on the determination
result. For example, the timer may be a signal connection release
indication (SCRI) timer for transmitting a SCRI message. Timer setup unit
416 may set up the SCRI timer with a comparatively short time when the
paging message is caused by the push data. Timer setup unit 416 may set
up the SCRI timer with a comparatively long time when the paging message
is caused by other events.

[0061] Transmitter 414 may transmit data to the radio access network. In
accordance with an exemplary embodiment of the present invention,
transmitter 414 may transmit a paging response message in response to the
paging message and a SCRI message to the radio access network. Controller
1118 may control overall operation of user equipment 110.

[0062] Hereinafter, a method for managing radio resources according to a
type of data in accordance with an exemplary embodiment of the present
invention will be described with reference to FIG. 5.

[0063] FIG. 5 illustrates a method for managing radio resources according
to a type of data in accordance with an exemplary embodiment of the
present invention.

[0064] Referring to FIG. 5, when SGSN 430 has data to be transmitted to
user equipment 410 in an idle mode, SGSN 430 may transmit a paging
message to user equipment 410 at step S500. For example, the paging
message may wake up user equipment 410 from the idle mode and transition
to a connected mode.

[0065] Upon receipt of the paging message, user equipment 410 may
determine a paging cause of the paging message at step S502. By
determining the paging cause, user equipment 410 may determine a type of
the data to be transmitted from SGSN 430. For example, timer setup unit
416 of user equipment 410 may determine whether the paging message is
caused by a push data based on the paging cause included in the paging
message. The present invention, however, is not limited thereto. Such
determination may be made after transmitting a paging response message to
SGSN 430.

[0066] In response to the paging message, a RRC connection may be
established between user equipment 410 and RNC 430 at step S504, and a
paging response message transmitted to SGSN 430 through the RRC
connection at step S506.

[0067] Upon the receipt of the paging response message, a RAB connection
may be established between SGSN 430 and RNC 430 at step S508, and a radio
bearer may be established between RNC 430 and user equipment 410 at step
S510. User equipment 410 may receive the data from SGSN 430 through the
RAB connection and the RRC connection at step 12

[0068] At step S514, user equipment 410 may set a timer based on the
determination result of step S502. That is, a period length of the timer
may be set according to a type of data transmitted from SGSN 430. For
example, when the type of data is a push data, user equipment 410 may set
the timer with a comparatively short time period in order to quickly
release radio resources allocated when establishing the RRC connection
and the RAB connection after receiving the push data. On the contrary
when the type of data is not a push data, user equipment 410 may set the
timer with a comparatively long time period in order to enable user
equipment 410 to transmit data in response to the received data. When the
type of data is not a push data, transmission of data to SGSN 430 in
response to the received data occurs with relatively high probability.

[0069] The timer may initiate release of the radio resources occupied
allocated when establishing the RRC connection and the RAB connection.
For example, the timer may be a. SCRI timer that may initiate
transmission of a SCRI message to RNC 420. The present invention,
however, is not limited thereto. The timer may initiate one or more other
signals or messages to invoke the RRC connection release procedure.

[0070] When user equipment 410 does not have data to be transmitted in the
period until the timer expires after receiving the data, a radio resource
release message may be transmitted to RNC 430 at step S516. For example,
the radio resource release message may be a SCRI message. In response to
the radio resource release message, RNC 430 may release the RAB
connection to SGSN 430 at step S518 and release the RRC connection to
user equipment 410 at step S520.

[0071] As described above, user equipment 410 may determine whether the
received data is a push data or not based on the paging cause included in
the paging message in accordance with an exemplary embodiment of the
present invention. When the received data is the push data, user
equipment 410 may set up the timer with a comparatively short time. User
equipment 410 may quickly release the radio resources occupied for the
RRC connection and the RAB connection right after receiving the push
data. Accordingly, radio resources may be further efficiently utilized
because the radio resources are quickly released when the received data
does not require user equipment 410 to transmit data in response to the
received data.

[0072] Particularly, when the connected mode is controlled by RRC states
such as a CELL_DCH state, a CELL_FACH state, and a CELL_PCH state, the
connected mode may not directly transition to the idle mode by
transmitting the SCRI message in accordance with an exemplary embodiment
of the present invention. For example, the CELL_DCH state is generally
unable transition to the idle mode without passing through the CELL_FACH
state and/or the CELL_PCH state. The CELL_DCH state may transit to the
CELL_FACH state when data traffic is not generated in the CELL_DCH state
for a given, predetermined period of time. The CELL_FACH state may
transition to the CELL_PCH state when data traffic is not generated for a
given time in the CELL_FACH state. The CELL_PCH state may transition to
the idle mode when data traffic is not generated for a given,
predetermined period of time in the CELL_PCH state. In accordance with an
exemplary embodiment of the present invention, the connected mode may
directly transition to the idle mode immediately after receiving a push
data by transmitting a SCRI message to RNC 430. Therefore, efficiency in
utilizing radio resources may be maximized in accordance with an
exemplary, embodiment of the present invention.

[0073] Reference herein to "one embodiment" or "an embodiment" means that
a particular feature, structure, or characteristic described in
connection with the embodiment can be included in at least one embodiment
of the invention. The appearances of the phrase "in one embodiment" in
various places in the specification are not necessarily all referring to
the same embodiment, nor are separate or alternative embodiments
necessarily mutually exclusive of other embodiments. The same applies to
the term "implementation."

[0074] As used in this application, the word "exemplary" is used herein
mean serving as an example, instance, or illustration. Any aspect or
design described herein as "exemplary" is not necessarily to be construed
as preferred or advantageous over other aspects or designs. Rather, use
of the word exemplary is intended to present concepts in a concrete
fashion.

[0075] Additionally, the term "or" is intended to mean an inclusive "or"
rather than an exclusive "or". That is, unless specified otherwise, or
clear from context, "X employs A or B" is intended to mean any of the
natural inclusive permutations. That is, if X employs A; X employs B; or
X employs both A and B, then "X employs A or B" is satisfied under any of
the foregoing instances. In addition, the articles "a" and "an" as used
in this application and the appended claims should generally be construed
to mean "one or more" unless specified otherwise or clear from context to
be directed to a singular form.

[0076] Moreover, the terms "system," "component," "module," "interface,",
"model" or the like are generally intended to refer to a computer-related
entity, either hardware, a combination of hardware and software,
software, or software in execution. For example, a component may be, but
is not limited to being, a process running on a processor, a processor,
an object, an executable, a thread of execution, a program, and/or a
computer. By way of illustration, both an application running on a
controller and the controller can be a component. One or more components
may reside within a process and/or thread of execution and a component
may be localized on one computer and/or distributed between two or more
computers.

[0077] The present invention can be embodied in the form of methods and
apparatuses for practicing those methods. The present invention can also
be embodied in the form of program code embodied in tangible media, such
as magnetic recording media, optical recording media, solid state memory,
floppy diskettes, CD-ROMs, hard drives, or any other machine-readable
storage medium, wherein, when the program code is loaded into and
executed by a machine, such as a computer, the machine becomes an
apparatus for practicing the invention. The present invention can also be
embodied in the form of program code, for example, whether stored in a
storage medium, loaded into and/or executed by a machine, or transmitted
over some transmission medium or carrier, such as over electrical wiring
or cabling, through fiber optics, or via electromagnetic radiation,
wherein, when the program code is loaded into and executed by a machine,
such as a computer, the machine becomes an apparatus for practicing the
invention. When implemented on a general-purpose processor, the program
code segments combine with the processor to provide a unique device that
operates analogously to specific logic circuits. The present invention
can also be embodied in the form of a bitstream or other sequence of
signal values electrically or optically transmitted through a medium,
stored magnetic-field variations in a magnetic recording medium, etc.,
generated using a method and/or an apparatus of the present invention.

[0078] It should be understood that the steps of the exemplary methods set
forth herein are not necessarily required to be performed in the order
described, and the order of the steps of such methods should be
understood to be merely exemplary. Likewise, additional steps may be
included in such methods, and certain steps may be omitted or combined,
in methods consistent with various embodiments of the present invention.

[0079] As used herein in reference to an element and a standard, the term
"compatible" means that the element communicates with other elements in a
manner wholly or partially specified by the standard, and would be
recognized by other elements as sufficiently capable of communicating
with the other elements in the manner specified by the standard. The
compatible element does not need to operate internally in a manner
specified by the standard.

[0080] No claim element herein is to be construed under the provisions of
35 U.S.C. §112, sixth paragraph, unless the element is expressly
recited using the phrase "means for" or "step for."

[0081] Although embodiments of the present invention have been described
herein, it should be understood that the foregoing embodiments and
advantages are merely examples and are not to be construed as limiting
the present invention or the scope of the claims. Numerous other
modifications and embodiments can be devised by those skilled in the art
that will fall within the spirit and scope of the principles of this
disclosure, and the present teaching can also be readily applied to other
types of apparatuses. More particularly, various variations and
modifications are possible in the component parts and/or arrangements of
the subject combination arrangement within the scope of the disclosure,
the drawings and the appended claims. In addition to variations and
modifications in the component parts and/or arrangements, alternative
uses will also be apparent to those skilled in the art.